package com.atguigu.gulimall.cart.interceptor;

import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberResponseVo;
import com.atguigu.gulimall.cart.to.UserInfoTo;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;
import static com.atguigu.common.constant.AuthServerConstant.LOGIN_USER;

/**
 * @author lk
 * @version 1.0.0
 * @Description 在执行目标方法之前，判断用户的登录状态.并封装传递给controller目标请求
 * @createTime 2024/2/22 11:28
 */
public class CartInterceptor implements HandlerInterceptor {
    public static ThreadLocal<UserInfoTo> toThreadLocal = new ThreadLocal<>();

    /***
     * 业务逻辑执行前，此方法执行
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();

        //获得当前登录用户的信息
        MemberResponseVo memberResponseVo = (MemberResponseVo)session.getAttribute(LOGIN_USER);
        if(memberResponseVo != null){
            //用户登录了
            userInfoTo.setUserId(memberResponseVo.getId());
        }
        //遍历cookies
        Cookie[] cookies = request.getCookies();
        if(cookies != null && cookies.length > 0){
            for(Cookie cookie:cookies){
                if(cookie.getName().equals(CartConstant.TEMP_USER_COOKIE_NAME)){
                    //封装user-key
                    userInfoTo.setUserKey(cookie.getValue());
                    //标记为已是临时用户
                    userInfoTo.setTempUser(true);
                }
            }
        }
        //如果没有临时用户一定分配一个临时用户
        if(StringUtils.isEmpty(userInfoTo.getUserKey())){
            String key = UUID.randomUUID().toString();
            userInfoTo.setUserKey(key);
        }
        //目标方法执行之前
        toThreadLocal.set(userInfoTo);
        return true;
    }

    /**
     * 业务执行之后，分配临时用户来浏览器保存
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        //获取当前用户的值
        UserInfoTo userInfoTo = toThreadLocal.get();
        //如果没有临时用户一定保存一个临时用户
        if(!userInfoTo.getTempUser()){
            //创建一个cookie
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
            //扩大作用域
            cookie.setDomain("gulimall.com");
            //设置过期时间
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        HandlerInterceptor.super.afterCompletion(request, response, handler, ex);
    }
}
